Del Rio was fired just one year after leading the team to a 12-4 record and the Raiders’ first playoff berth in well over a decade.

Indeed, Del Rio’s departure comes less than a year after he signed a new four-year extension; in announcing the deal, Raiders owner Mark Davis said the initial four-year deal Del Rio signed upon his hiring in 2015 had been “torn up” and that he was “excited to continue building on the strong foundation that’s been established.”

Farewell: Jack Del Rio announced after the Oakland Raiders’ loss to the Los Angeles Chargers that he’d been fired by owner Mark Davis. (AP)

The foundation, apparently, crumbled in a matter of months.

Davis’ decision to part ways with Del Rio also gives credence to the “grumors” that began swirling on Saturday night that Davis wanted to bring Jon Gruden back to the organization. Stories about Gruden, who hasn’t coached in a decade, returning to the sideline have become an annual tradition, but perhaps this time there’s actually some traction to them.

Unable to maintain their momentum from last season – they were quickly eliminated from the playoffs, after a late-season injury to Derek Carr rendered him unavailable – the Raiders had a disappointing season in 2017, eliminated from playoff contention with two games left to play, and they finished 6-10.

Del Rio did what he could to try and turn things around, firing defensive coordinator Ken Norton Jr. on Nov. 21, after the team’s 33-8 loss to the New England Patriots. John Pagano, who was on the staff as assistant head coach-defense, took over as coordinator.

The switch did work, at least statistically: over their first 10 games, with Norton running the defense, the Raiders allowed 367 yards per game, including 113.8 rushing yards and 253.2 passing yards, and they were 31st in the league on third down, allowing 46.0 percent (63-of-137); since then, a span of five games, they’ve been allowing 287.2 yards per game (98.0 rushing, 189.2 passing), and have been much stronger on third downs, allowing conversions on 18-of-65 chances (27.7 percent).

But the bigger issue for Oakland may have been on offense. Under first-year coordinator Todd Downing, the group appeared to take a step back, particularly Carr and receiver Amari Cooper. Downing served as quarterbacks coach for the 2015-16 seasons, so perhaps the increased workload as play-caller overwhelmed him, but the difference in the offense’s performance from last year to this is stark: Carr more than doubled his interceptions, with 13 this year after just six in 2016. Other marks, like completion percentage and yards per attempt, saw a dip.

Amari Cooper, who had a Pro Bowl season in 2016, had a significant drop in his output, as did Michael Crabtree; last year, that pair combined for over 2,100 receiving yards on 172 catches. Some of that might be attributed to the addition of tight end Jared Cook, but a solid tight end, in theory, should have made the offense better.

The Raiders are essentially a dead team walking in Oakland, as 2018 could be their last season in the city before moving to Las Vegas, so perhaps firing Del Rio was done with the idea of keeping fans interested in mind.